Safety ski binding system

ABSTRACT

A connection between the ski and the skiing boot is provided for by a separate soleplate. A plate-holding device engages the soleplate behind the heel of the boot. An abutment for the soleplate is mounted on the ski. The plate-holding device normally urges the soleplate against the abutment and releases the same in response to an overload acting in a vertical and/or horizontal direction. The abutment consists of a lever, which is pivoted to the ski on an axis which is transverse to the longitudinal direction of the ski. Said lever has a free end portion extending toward the rear end of the ski. A disc is provided on the underside of the soleplate and is adapted to be approximately coaxial to the tibia of the skier and bears on the free end portion of the lever. At least two bearing blocks are secured to the ski below the soleplate and support the soleplate before and behind the disc. The plate-holding device comprises a known, spring-loaded detent member, which engages a wedge-shaped notch at the rear end of the soleplate. The apex of said notch is rearwardly and downwardly inclined.

ite States ate Fend [451 Aug. 14, .1973

[ SAFETY SKI BINDING SYSTEM [75] Inventor: Fritz M. Fend, Regensburg,

- Germany [73] Assignee: Hannes Marker,

Garmisch-Partenkirchen, Germany [22] Filed: June 8, 1971 21] Appl. No.:150,974

[30] Foreign Application Priority Data June 23, 1970 Germany P 20 31018.3

[52] US. Cl. 2811/1135 K [51] Int. Cl. A63c 9/00 [58] Field of Search280/11.35 K, 11.35 T,

280/11.35 Y, 11.35 R, 11.35 A, 11.35 E, 11.35 C, 11.35 D

Primary Examiner-Kenneth 1-1. Betts Assistant Examiner-ReinhardEisenzopf Attorney-Fieit, Gipple & Jacobson [5 7] ABSTRACT A connectionbetween the ski and the skiing boot is provided for by a separatesoleplate. A plate-holding device engages the soleplate behind the heelof the boot. An abutment for the soleplate is mounted on the ski. Theplate-holding device normally urges the soleplate against the abutmentand releases the same in response to an overload acting in a verticaland/or horizontal direction. The abutment consists of a lever, which ispivoted to the ski on an axis which is transverse to the longitudinaldirection of the ski. Said lever has a free end portion extending towardthe rear end of the ski. A disc is provided on the underside of thesoleplate and is adapted to be approximately coaxial to the tibia of theskier and bears on the free end portion of the lever. At least twobearing blocks are secured to the ski below the soleplate and supportthe soleplate before and behind the disc. The plate-holding devicecomprises a known, spring-loaded detent member, which engages awedge-shaped notch at the rear end of the soleplate. The apex of saidnotch is rearwardly and downwardly inclined.

7 Claims, 4 Drawing Figures PAIENIEnAus 14 I975 SHEET 1 BF 2 INVENTOR:

PATENIEIJMI: 14 ms SHEET 2 BF 2 WM w SAFETY SKI BINDING SYSTEM Thepresent invention relates to a safety ski binding system, in which aconnection between the ski and the skiing boot is provided for by aseparate soleplate and which comprises a plate-holding device, whichengages the soleplate behind the heel of the boot, and an abutment forthe soleplate, which abutment is mounted on the ski, and theplate-holding device normally urges the soleplate against the abutmentand releases the same in response to an overload acting in a verticaland/or horizontal direction.

Compared to the known, commercially available safety ski bindings, inwhich the skiing boot is held by safety release elements directlyengaging the sole of the boot, this safety ski binding system has theadvantage that the forces required for a release are independent of theshape and elasticity of the sole of the boot because the safety releaseelements engage the additional soleplate. Besides, the adjustment of agiven force required for a release is simpler and faster because thereis only a single release element for twisting and forward falls.

A known ski binding which has been described as a plate binding has theimportant disadvantage that the soleplate may become seized between therelatively Widely spaced points where it is gripped. Such seizing mayoccur, e.g., when the ski moves through a depres sion. At that time, theforces by which the plate is re tained on the ski may increase sohighly'that any dangerous twisting movement which may be performed doesnot result in the required release so that the risk of a dangeroustorsional fracture of the tibia is greatly increased. On the other hand,the retaining forces are often smaller than required during normalskiing if the required margin of safety is taken into account.

It is an object of the invention to provide a safety ski binding systemwhich combines the advantages of the known ski bindings but is free oftheir disadvantages.

In a safety ski binding system, in which a connection between, theskiand the skiing boot is provided for by a separate soleplate and whichcomprises a plateh olding device,-which engages the soleplate behind theheel of the boot, and an abutment for the soleplate,

which abutment is mounted on the ski, and in which the.

platerholding device normally urges the soleplate against the abutmentand releases the same in response to anoverload acting in a verticaland/or horizontal direction, this object is accomplished in that theabutment consists of a lever, which is pivoted to the ski on an axiswhich is transverse to the longitudinal direction of the ski, said leverhas a free end portion extending toward the rear end of the ski, a discis provided on the underside of the soleplate and approximately coaxialto the tibia and bears on the free end portion of the lever, at leasttwo bearing blocks are secured to'the ski below the soleplate andsupport the soleplate before and behind the disc, the plate-holdingdevice comprises a known, spring-loaded detent member, which engages awedge-shaped notch at the rear end of the soleplate, and the apex ofsaid notch is rearwardly and downwardly inclined. In this arrangement,the soleplate is normally held in position on the ski but under theaction of forces which are dangerous to the skier's leg the skiing bootand the, plate can always detach from the ski equally well and with thesame ease regardless of the direction of said forces. Even when the skiis exing system shown in FIG. I,

tremely deflected by some external influence, a release of the soleplatewill not be prevented because the distance between the points where theplate is gripped is minimized.

In a development of the invention, it has proved particularly desirableto provide a disc which is round and a pivoted lever which at its freeend has a recess, the edge of which normally embraces part of theperiphery of the disc. As a result, the soleplate and the skiing bootare freely rotatable relative to the ski during a twisting fall of theskier, and during normal skiing the controlling forces exerted by theskiers leg are transmitted to the ski positively and directly in such amanner that the safety release element is by-passed.

To facilitate the application of the soleplate to the ski and therotation of the soleplate to its correct position, in which thesoleplate is parallel to the ski, when the skis are reapplied, e.g.,after a fall of the skier, it has proved desirable to provide acentering plate, which is secured to the ski on that side of the discwhich is opposite to the lever, and which centering plate at that endwhich faces the disc has a recess, which has the shape of an arc of acircle having the same radius at the disc, and the edge of whichembraces the disc with a clearance.

The sum of the frictional forces between the soleplate and itsbearings'assists the resistance presented by the spring. To prevent achange of that sum when the weight of the skier is shifted, the bearingblocks are preferably spaced equal distances apart from the axis ofrotation of the plate. It is desired to compensate an increase of thesefrictional forces even when the plate has been lifted from the rearbearing block. For this purpose, the included angle of the wedge-shapednotch may, in accordance with a feature of the invention, 'decreasecontinuously in a downward vertical direction.

If a retaining element is desired to provide for an additionalconnection between the ski and the soleplate, this additional connectionmay be provided for by two elastic strips, which are disposed below thesoleplate and on both sides of the disc and extend parallel to thelongitudinal direction of the ski, and each of said strips may have oneend which is secured to the ski and another end secured to the undersideof the plate, in such a manner that that end of each strip which isnearer to the disc is secured to the ski. The ends of the elastic stripsmay be articulatedly connected to the ski and to the soleplate and thecentering plate may serve as one of the means for securing the strips tothe ski.

An embodiment of the invention will now be described more fully and byway of example with refer ence to the accompanying drawings, in which.

FIG. 1 is a central longitudinal sectional view showing the safety skibinding system,

FIG. 2 is a top plan view showing the safety ski bind- FIG. 3 is atransverse sectional view taken through the safety ski binding system ofFIG. 1 and taken on line III-III thereof, and

FIG. 4 shows the safety ski binding system in a position at the upperlimit of its elastic range.

The safety ski binding system which is shown com prises a channel-shapedsoleplate 1 (see particularly FIG. 3), which has upstanding flanges 2.The skiing boot 3 is secured on top of the soleplate 1 between theflanges 2 thereof so that the boot can be only arbitrarily detached fromthe soleplate. For this purpose, a known heel tightener lever 4 isprovided, which is pivoted to the rear end of the plate 1 and comprisestightener cables 5, which are secured to the flanges 2 ofthe soleplate1, and a toe iron 6, which has a horizontal arm 7 engaging the toeportion of the sole of the skiing boot. The tightener lever 4 isoperable to force the skiing boot against the toe iron 6. To enable afixation of different sizes of skiing boots to the soleplate l, the toeiron 6 is mounted on the flanges 2 of the plate 1 in such a manner thatit is adjustable in the longitudinal direction of the plate 1. For thispurpose the toe iron comprises two rearwardly extending arms 8, whichengage the flanges 2 of the soleplate on the outside. Each of the arms 8is provided on the inside with vertical serrations or rough portions 9and is also provided with two horizontally extending slots 10. Theforward portions of the flanges 2 of the soleplate l are provided on theoutside with a corresponding serration or rough portion 11. The toe iron6 can be secured in the desired position by means of four threaded bolts12, which are secured in the flanges 2 of the soleplate and extendoutwardly through the slots 10 in the arms 8, and by nuts 13, which arerespectively threaded on said bolts. An adaptation to the thickness ofthe sole is generally required only once. For this purpose, thehorizontal arm 7 of the toe iron 6 is bent in an upward or downwarddirection to the desired extent. An adaptation to heels having differentheights is enabled in that the tightener cables 5 of the heel tightener4 can be secured to the rear end portions of the plate flanges atdifferent points. For this purpose, each plate flange 2 is provided withfour bores 14.

In the normal position shown in FIGS. 1 and 2, the soleplate l issupported by three bearing blocks 15, which are secured to the ski 16.These bearing blocks are screw-connected or adhesively bonded to the skiby means which are not shown. At least the upper surface of the bearingblocks consists of low-friction material, such as teflon.

Two substantially channel-shaped bearing brackets 17 are secured on topof the ski 16 below the soleplate l and have upstanding flanges. A pivot18 is nonrotatably held between the flanges of each of said bearingbrackets. In accordance with the invention, a lever 19 is pivoted onsaid pivots. The lever 19 comprises two supporting arms 20, whichnormally extend in the longitudinal direction of the ski toward the rearend of the ski, and a crosspiece 21 at the end of the supporting arms. Arecess 23 (see particularly FIG. 2) is provided on that side of thecrosspiece 21 which faces the rear end of the ski. The edge of saidrecess has a portion defined by an arc of a circle and two portionsdefined by straight lines which tangentially merge into the arcuateportion. The soleplate 1 is provided with a circular disc 24, whichenters the recess 23 so that the soleplate 1 bears on the lever 19 inthe direction toward the tip of the ski. The circular disc 24 is rivetedto the underside of the soleplate 1 adjacent to the axis of the tibiaand at its peripheral surface is formed with a closed annular groove 25,which has a rounded cross-section and is in mating contact with the alsorounded edges of the recess 23 of the lever 19.

A plate-holding device 30, which is known and for this reason will notbe described more fully, is screwconnected to the ski 16 behind thesoleplate l. The plate-holding device 30 comprises a detent member 31,which is biased by a spring 36. The detent member 31 consists of aballand engages a wedge-shaped notch 32, which is formed in a bracket33, which is secured by screws 34 to the rear end of the plate. Toensure a rigid connection of the bracket 33 to the soleplate 1, thebracket is provided with a slot in which the soleplate is engaged. Thewedge-shaped notch 32 is disposed at the rear end of the bracket and hasan apex 35 which is rearwardly and downwardly inclined (see FIG. 1) sothat in the normal position the detent member 31 lies in the upperportion of the notch. When the binding is ready for skiing, thespring-biased detent member 31 urges the disc 24 of the soleplateagainst the lever 19, which constitutes a forward abutment.

To prevent a lifting of the forward end of the soleplate 1 from the ski16 when the soleplate is parallel to the ski, a Z-shaped angledholding-down member 40 is mounted on the ski between the forward bearingblocks 15. One flange 41 of the holding-down member 40 isscrew-connected to the ski. The upper flange 42 of the member 40 isspaced from the surface of the ski and extends toward the tip of theski. As is apparent from FIG. 2, the upper flange 42 is pointedforwardly and is rounded in the horizontal and vertical directions. Atongue 43 has been struck from the soleplate 1 and bent downwardly andreawardly engages the underside of the tip of the upper flange of theholding-down member (see particularly FIG. 1).

Two elastic strips 45 are provided, each of which has one end which isarticulatedly connected to the ski and another end which isarticulatedly secured to the underside of the soleplate so that thesoleplate remains connected to the ski 16 also when the plate-holdingdevice 30 has been unlocked because the detent member 31 no longerengages the notch 32 in the soleplate. The elasticity of these retainingstrips 45 is so large that the movement performed by the soleplate 1when the safety ski binding system is released is not appreciablyhindered.

The manipulation of the binding system is extremely simple. The skierapplies the skiing boot to the soleplate 1, which has normally beensecured to the ski in the correct manner. The skier then pushes the toeportion of his boot under the horizontal arm 7 of the toe iron 6 andthereafter applies the roller provided at the lower end of the heeltightener 4 onto the heel of the skiing boot and swings up this leverbeyond its dead center position so that the upper end of the leverengages the upper of the skiing boot at a point above the heel of theski boot. The skiing boot 3 is now firmly secured to the plate 1. Whenthe skiing boot is to be disconnected from the plate, it is sufficientto swing back the tightener lever 4 beyond its dead center position,e.g., by means of a skiing boot.

If during skiing a force which is directed upwardly and at right anglesto the surface of the ski acts on the skiers leg and on the soleplate land said force exceeds the initial stress of the spring 36 which biasesthe detent member 31, the rear end of the soleplate 1 will swingupwardly about the forward bearing blocks 15. As is clearly apparentfrom FIG. 3, the lever 19 which serves as a forward abutment for thesoleplate l swings also upwardly because the forward pressure applied bythe detent member 31 continues to force the disc 24 into the recess 23.

If the force does not increase to the value of the set force requiredfor a release or if it acts only as a shock and decreases before thedetent member 31 has left the notch 32, the spring force aided by theweight of the skicr forces the soleplate I back to its initial positionand the lever 19 also swings back to its normal position.

If a force which is vertically upwardly directed and which is dangerousfor the skier's leg acts on the skiing boot not only as a shock, thesoleplate 1 will swing first to the position shown in FIG. 3, as hasbeen described hereinbefore. As the pivotal movement of the soleplate iscontinued, the detent member 31 leaves the notch 32 so that thesoleplate 1 can move substantially freely relative to the ski and candisengage the abutment lever 19 because the pressure from the rear issuddenly eliminated at this time. The elastic strips prevent a completedisconnection of the ski from the skiers foot.

Under the action of forces which are directed transversely to thelongitudinal direction of the ski and which exceed the initial stress ofthe spring 36, the plate swings about the axis of the disc 24 so thatthe latter turns in the recess 23 of the lever 19. The detent memberthen runs up on one side of the notch 32. If the force decreases beforethe detent member 31 has disengaged the notch 32, the spring 36 willreturn the detent member 31 to its central position into the notch 32 sothat the soleplate 1 also swings backs to its normal position.

If an excessive force in a direction which is transverse to thelongitudinal direction acts not only as a shock, the plate 1 will turnin the manner described hereinbefore until the detent member 31 leavesthe notch after a predetermined elastic movement, which is determined bythe lateral extension of the sides of the notch. The plate can then alsomove freely relative to the ski.

It will be understood that the action of a force on the heel of theskiing boot in an upwardly inclined direction, e.g., in the case of adiagonal fall of the skier, the horizontal and vertical movements of theplate will be superposed and will reliably cause the same to be releasedwhen the force reaches a value which is dangerous to the skiers leg.

When the soleplate has been released, e.g., after a fall, and the skierdesires to re-apply the ski, he holds the skiing boot 3 an the soleplate1 connected thereto to extend transversely to the ski 16 and applies thesoleplate to the ski so that the disc 24 is received in the recess 23.The skiing boot 3 together with the plate 1 is then turned so that thedetent member slides on the corresponding oblique outside surface of thenotched bracket 33 until the detent member 31 falls into the notch 32.

To facilitate the application of the skis, a centering plate 46 issecured to the ski 16 on that side of the disc 24 which is opposite tothe lever 19. At that end of the centering plate 46 which faces the disc24, the centering plate 46 has a recess 47, which is defined by an arcof a circle having approximately the same radius as the disc. Theclearance between the recess 23 in the lever 19 and the recess 47 in thecentering plate 46 is so large that the disc 24 is embraced with aclearance when the soleplate l is applied to the ski 16.

To ensure that a shifting of the weight of the skier will not result ina change of the torsional friction between the soleplate 1 and thebearing blocks 15, which torsional friction is to be overcome during arelease in response to a twisting or diagonal fall, the bearing blocksare spaced equal distances apart from the axis of rounion olthc plate,more particularly, of the disc. ln this case, the sum of the torsionalfriction forces acting at the bearing blocks will remain constant aslong as the plate rests on both bearing blocks. In order to maintainthis friction constant even when the soleplate has been lifted from therear bearing block, the notch is designed so that its wedge angledecreases downwardly so that an increase of the friction can becompensated by a decrease of the spring bias applied to theplate-holding device until the plate is released.

What is claimed is:

1. A safety ski binding comprising a soleplate adapted to receive theskiing boot of a skier, said soleplate having a wedge-shaped notchassociated with the rear end of the soleplate, an abutment mounted onthe ski comprising a lever having one end pivoted to the ski on an axiswhich is transverse to the longitudinal direction of the ski and havinganother end which is unattached to the ski and extends toward the rearof the ski, a disc mounted on the underside of the soleplate and adaptedto be approximately coaxial to the tibia of the skier, bearing meansmounted on the ski below the soleplate such that the soleplate can bearon the bearing means in front of and behind the disc, and means adaptedto engage the rear of the soleplate and to urge the disc against theunattached end of the lever and to release the soleplate in response toan overload force, said means comprising detent means and spring meansadapted to urge said detent means against the wedgeshaped notch.

2. The safety ski binding of claim 1 in which the disc is round and theunattached end of the lever has a recess which normally engages part ofthe periphery of the disc.

3. The safety ski binding of claim 2 and further comprising a centeringplate mounted on the ski on the opposite side of the disc from the leverand in which the centering plate has a recess facing the disc havingpart of the arc of a circle having the same radius as the radius of thedisc and in which the recess of the centering plate embraces the discand is spaced therefrom.

4. The safety ski binding of claim 1 in which the bearing means in frontof the disc compriSe bearing blocks sapced equal distances apart fromthe axis of rotation of the soleplate.

5. The safety ski binding of claim 1 in which the wedge-shaped notch hasa wedge angle which is continuously decreasing in the downward verticaldirection.

6. A safety ski binding of claim 3 and further comprising retainingmeans providing an additional connection between the ski and thesoleplate, said retaining means comprising two elastic strips positionedbelow the soleplate and on both sides of the disc and extending parallelto the longitudinal direction of the ski, each of said strips having oneend mounted on the ski and the other end mounted on the underside of thesoleplate in such a manner that the end of the strip which is nearer tothe disc is mounted on the ski.

7. The safety ski binding of claim 6 in which the ends of the elasticstrips are articulately connected to the ski and to the soleplate and inwhich the centering plate serves as one of the means for securing thestrip to the ski.

1. A safety ski binding comprising a soleplate adapted to receive theskiing boot of a skier, said soleplate having a wedge-shaped notchassociated with the rear end of the soleplate, an abutment mountEd onthe ski comprising a lever having one end pivoted to the ski on an axiswhich is transverse to the longitudinal direction of the ski and havinganother end which is unattached to the ski and extends toward the rearof the ski, a disc mounted on the underside of the soleplate and adaptedto be approximately coaxial to the tibia of the skier, bearing meansmounted on the ski below the soleplate such that the soleplate can bearon the bearing means in front of and behind the disc, and means adaptedto engage the rear of the soleplate and to urge the disc against theunattached end of the lever and to release the soleplate in response toan overload force, said means comprising detent means and spring meansadapted to urge said detent means against the wedge-shaped notch.
 2. Thesafety ski binding of claim 1 in which the disc is round and theunattached end of the lever has a recess which normally engages part ofthe periphery of the disc.
 3. The safety ski binding of claim 2 andfurther comprising a centering plate mounted on the ski on the oppositeside of the disc from the lever and in which the centering plate has arecess facing the disc having part of the arc of a circle having thesame radius as the radius of the disc and in which the recess of thecentering plate embraces the disc and is spaced therefrom.
 4. The safetyski binding of claim 1 in which the bearing means in front of the disccompriSe bearing blocks sapced equal distances apart from the axis ofrotation of the soleplate.
 5. The safety ski binding of claim 1 in whichthe wedge-shaped notch has a wedge angle which is continuouslydecreasing in the downward vertical direction.
 6. A safety ski bindingof claim 3 and further comprising retaining means providing anadditional connection between the ski and the soleplate, said retainingmeans comprising two elastic strips positioned below the soleplate andon both sides of the disc and extending parallel to the longitudinaldirection of the ski, each of said strips having one end mounted on theski and the other end mounted on the underside of the soleplate in sucha manner that the end of the strip which is nearer to the disc ismounted on the ski.
 7. The safety ski binding of claim 6 in which theends of the elastic strips are articulately connected to the ski and tothe soleplate and in which the centering plate serves as one of themeans for securing the strip to the ski.